Cholera Toxins. Produced by Vibrio cholerae, cholera toxin (CT) is a multimeric enterotoxin that transfers ADP-ribose to a G protein, locking adenylate cyclase in an 'on' position.
echinoderm. n. 1. (Animals) any of the marine invertebrate animals constituting the phylum Echinodermata, characterized by tube feet, a calcite body-covering (test), and a five-part symmetrical body. The group includes the starfish, sea urchins, and sea cucumbers.ny of various invertebrate sea animals having a hard spiny outer covering, an internal skeleton, and a radially symmetrical body. Starfish, sea urchins, and sea cucumbers are echinoderms.
Echinoderms evolved from animals with bilateral symmetry. Although adult echinoderms possess pentaradial, or five-sided, symmetry, echinoderm larvae are ciliated, free-swimming organisms that organize in bilateral symmetry which makes them look like embryonic chordates.ll echinoderms are marine and nearly all are benthic. The oldest known echinoderm fossil may be Arkarua from the Precambrian of Australia. It is a disc-like fossil with radial ridges on the rim and a five-pointed central depression marked with radial lines.